[tbb-bugs] #23453 [Applications/Tor Browser]: Unable to Handle Google Groups page with 5000 Discussion Threads

[Tor Bug Tracker & Wiki]

#23453: Unable to Handle Google Groups page with 5000 Discussion Threads
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     Reporter:  grassgreen                |      Owner:  tbb-team
         Type:  defect                    |     Status:  new
     Priority:  Medium                    |  Milestone:
    Component:  Applications/Tor Browser  |    Version:  Tor: unspecified
     Severity:  Normal                    |   Keywords:
Actual Points:                            |  Parent ID:
       Points:                            |   Reviewer:
      Sponsor:                            |
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 The use case is not to anonymize the user, but
 to hide the user's location, for example, during traveling.


 TorBrowser verson:  64bit, Linux, 7.0.5, based on Mozilla Firefox 52.3.0


 Reproduction:

 step 1:
 Log in to some Google Group that has at least 5000 threads,
 possibly with the first threads being very old.

 step 2:
 Open a few more tabs, may be the list of users, may be
 some threads with posts.

 step 3:
 Reduce the available CPU time by playing some video
 in the background, but make sure that there will
 be enough RAM left so that the swapping will not
 kick in and the video really consumes only
 CPU time, not RAМ from the TorBrowser.

 step 4:
 Try switch between the different TorBrowser tabs
 and try to scroll the Google Groups lists.
 The scrolling will temporarily jam, CPU consumption
 of the TorBrowser goes high and after some waiting
 the Google Groups list scrolling will work again fluently at the
 opened TorBrowser tab, but after a switch to
 another tab that also displays a google groups scrolling
 widget, which does not need to include a very long list,
 even scrolling of the short list of items jams. The
 jam can be waited out and then, after the current tab
 works fine, the previous one that previously worked fluently,
 jams again.

 step 5:
 The switching of tabs can be repeated. All of that
 without triggering swapping.


 Suspicion:

 It might be related to the rendering engine
 of the Firefox browser. People at Google probably
 just test the Google web services only with their
 own Google Chrome and they don't go to such extremes.

 As the Mozilla Thunderbird mail reader is also based
 on the Firefox code base, the scrolling related issues
 of the Mozilla Thunderbird might also be related to the
 Firefox rendering engine. For example, the Mozilla Thunderbird
 mail reading program jams, when it tries to display an
 email that has millions of ASCII characters in a single line.


 Practical Philosophy:

 The Mozilla Corporation is a huge corporation and if they,
 with all of their resources, can let such basic things
 slip through, then clearly they are not interested fixing it.
 The TorBrowser team is smaller and slicker, so the only
 chance of getting that fixed is the TorBrowser team.
 May be You can offer the patches to the Mozilla Corporation later.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/23453>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online